Blow molded plastic aerosol container

ABSTRACT

A plastic container for holding aerosol contents under pressure includes a one-piece integrally molded plastic body having a base, a sidewall and a neck finish. The sidewall and the base are of oval cross-section, and the base has a contour and cross-section for maintaining the oval cross-section under aerosol pressure within the container body. The neck finish has an open mouth surrounded by a circumferentially continuous external bead for securing a dispensing closure. The bead has an undersurface that is perpendicular to an axis of the neck finish, and the neck finish has a chamferred inside edge around the open mouth to facilitate insertion of a dispensing closure.

The present invention relates to aerosol packages in which the containeris adapted to hold contents under pressure, and more particularly to ablow molded plastic container for such a package.

BACKGROUND AND SUMMARY OF THE INVENTION

Containers for aerosol packages typically are of glass or metalconstruction so as to possess sufficient strength to hold the packagecontents under pressure without distortion of the container. A generalobject of the present invention is to provide a blow molded plasticcontainer for aerosol package applications in which the container bodyhas an oval cross-section, in which the container base is contoured toretain the oval cross-section of the container body under aerosolpressure, and in which the neck finish is particularly well adapted tofacilitate handling during manufacture.

A plastic container for holding aerosol contents under pressure inaccordance with presently preferred embodiments of the inventionincludes a one-piece integrally molded plastic body having a base, asidewall and a neck finish. The sidewall and the base are of ovalcross-section, and the base has a contour and cross-section formaintaining the oval cross-section under aerosol pressure within thecontainer body. The neck finish has an open mouth surrounded by acircumferentially continuous external bead for securing a dispensingclosure. The bead has an undersurface that is perpendicular to an axisof the neck finish, and the neck finish has a chamferred inside edgearound the open mouth to facilitate insertion of a dispensing closure.In the preferred embodiments of the invention, the neck finish includesa support flange spaced from the external bead. The support flange has aperipheral edge with at least one locating element for orienting theoval cross-section in automated equipment for assembling the dispensingclosure to the container. The base preferably is a champagne base havinga central outwardly oriented convex portion and a peripheral standingring. The standing ring preferably has a thickness that is 2 to 2.5times the thickness of the container sidewall.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention, together with additional objects, features, advantagesand aspects thereof, will best be understood from the followingdescription, the appended claims and the accompanying drawings, inwhich:

FIG. 1 is a front elevational view of a container in accordance with onepresently preferred embodiment of the invention;

FIG. 2 is a side elevational view of the container in FIG. 1;

FIG. 3 is a partially sectioned top plan view of the container in FIG.1;

FIG. 4 is a fragmentary sectional view on an enlarged scale of theportion of FIG. 3 within the area 4;

FIG. 5 is a fragmentary sectional view on an enlarged scale of theportion of FIG. 2 within the area 5;

FIG. 6 is a fragmentary sectional view that illustrates the base of thecontainer in FIGS. 1-3;

FIG. 7 is a front elevational view of a container in accordance withanother embodiment of the invention;

FIG. 8 is a partially sectioned top plan view of the container in FIG.7;

FIG. 9 is a fragmentary sectional view of the portion of FIG. 8 withinthe area 9; and

FIG. 10 is a sectional view of an aerosol dispensing closure that can beused with the container of FIGS. 1-6 or FIGS. 7-9.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIGS. 1-6 illustrate a container 20 in accordance with one presentlypreferred embodiment of the invention. Container 20 is of one-pieceintegrally blow molded construction having a body 22 with a base 24, asidewall 26 and a neck finish 28. Sidewall 26 and base 24 are of ovalconstruction, as best seen in FIG. 3. Neck finish 28 is cylindrical andhas a circumferentially continuous external bead 30 that surrounds theopen mouth of the container. Bead 30 has an undersurface 32 that is flatand planar on an axis perpendicular to the axis of the neck finish. Flatundersurface 32 provides positive alignment with in-feed and out-feedjaws on two-stage reheat stretch blow molding equipment. Furthermore,undersurface 32 provides for secure crimping of an aerosol dispensingclosure (FIG. 10). The inside diameter of the container mouth, at theopen end of neck finish 28, is chamferred at 34 (FIG. 5) to facilitateplacement and securement of the dispensing closure (e.g. FIG. 10).

Neck finish 28 preferably also includes an external support flange 36,sometimes termed a capping flange or a transfer flange, spaced from theopen mouth of the container. Flange 36 is circumferentially continuousand perpendicular to the axis of the neck finish. Flange 36 has aperipheral edge that preferably includes at least one locating element38 for orienting the oval cross-section of container 20. In theembodiment of FIGS. 1-6, the locating element 38 is a notch on theperiphery of the flange aligned with the minor axis of the ovalcontainer cross-section, as best seen in FIG. 3. Notch 38 can be used byautomated capping equipment for locating the dispensing closureangularly with respect to the container finish so that the closuredispenses product at a desired orientation with respect to the containercross-section, such as in the direction of the minor axis of thecontainer.

The preferred construction of container base 24 is illustrated in FIG.6. Base 24 preferably is a so-called champagne base, having an outwardlyconvex central portion or dome 40 and a peripheral standing ring 42. Thethickness 44 of standing ring 42 preferably is 2 to 2.5 times thethickness 46 of container sidewall 26. Base 24 is designed to rigidifythe container sidewall and maintain the oval contour of the containersidewall under pressure within the container. The thickness contour ofbase 24 can be designed either to have a constant thickness profilearound the axis of the container, or to have two unique profiles at themajor and minor axes of the container cross-section that are blendedwith each other between the major and minor axes.

FIGS. 7-9 illustrate a container 50 in accordance with a secondembodiment of the invention. Container 50 is essentially the same ascontainer 20 in FIGS. 1-6 except for the locating elements on the neckfinish support flange 36. In the embodiment of FIGS. 7-9, the locatingelements on the support flange comprise a pair of outwardly extendinglugs 52 on diametrically opposed sides of neck finish 28 at the minoraxis of the oval container cross-section.

FIG. 10 illustrates a conventional aerosol dispensing closure 60, whichincludes a metal ring 62 that is crimped over bead 30 for securing thedispensing closure to the aerosol container of the present invention.

The container of the present invention can be made employing anysuitable manufacturing technique. The container preferably is made in areheat blow molding process, in which a preform is first constructedsuch as by injection or compression molding, and the preform is thenreheated and blow molded to form the container body. The container neckfinish, including bead 30 and support flange 36, preferably are formedat the preform stage. The container can be of any suitable plasticmaterial such as polyethylene terephthalate (PET), and can be ofmonolayer construction or multilayer construction that includes one ormore internal barrier layers such as nylon or ethylene vinyl alcohol(EVOH). According to another feature of the invention, one of the layersof a multilayer sidewall construction can have a high glass transitiontemperature Tg, which helps resist deformation of the container body.For example, the container sidewall can have a two-layer construction:(1) PET having a thickness of 0.042 inch and a glass transitiontemperature of 70C, and (2) amorphous nylon having a thickness of 0.028and a glass transition temperature of 115C.

There thus have been disclosed a plastic container and a method ofmaking a plastic container, which are particularly well-suited foraerosol applications and which fully satisfy all of the objects and aimspreviously set forth. The invention has been disclosed in conjunctionwith two presently preferred embodiments, and a number of modificationsand variations have been discussed. Other modifications and variationsreadily will suggest themselves to persons of ordinary skill in the artin view of the foregoing disclosure. The invention is intended toembrace all such modifications and variations as fall within the spiritand broad scope of the appended claims.

1. A plastic container for holding aerosol contents under pressure,which includes: a one-piece integrally molded plastic body having abase, a sidewall and a neck finish, said sidewall and said base being ofoval cross-section, and said base having a contour and cross-section formaintaining said oval cross-section under pressure within said body,said neck finish having an open mouth surrounded by a circumferentiallycontinuous external bead for securing a dispensing closure, said beadhaving a flat undersurface perpendicular to an axis of said neck finish,said neck finish having a chamferred inside edge around said open mouthto facilitate attachment of a dispensing closure.
 2. The container setforth in claim 1 wherein said neck finish includes a support flangespaced from said external bead.
 3. The container set forth in claim 2wherein said support flange has a peripheral edge with at least onelocating element for orienting said oval cross-section.
 4. The containerset forth in claim 3 wherein said at least one locating element ispositioned on a minor axis of said oval cross-section.
 5. The containerset forth in claim 4 wherein said at least one locating element includesa pair of locating elements on opposed sides of said neck finish alongsaid minor axis.
 6. The closure set forth in claim 4 wherein said atleast one locating element is a notch or a lug.
 7. The container setforth in claim 1 wherein said base is a champagne base having a centraloutwardly convex portion and a peripheral standing ring.
 8. Thecontainer set forth in claim 7 wherein said standing ring has athickness that is 2 to 2.5 times the thickness of said sidewall.
 9. Thecontainer set forth in claim 1 wherein said body is of multilayerconstruction including at least one relatively thick layer of a firstmaterial, and at least one relatively thin layer of a second materialhaving a higher glass transition temperature than said first materialfor retaining the oval cross-section of the container body.
 10. A methodof making a plastic container that includes the step of blow molding aone-piece plastic body having a base, a sidewall and a neck finish, saidsidewall and said base being of oval cross-section, and said base havinga contour and cross-section for maintaining said oval cross-sectionunder pressure within said body, said neck finish having an open mouthsurrounded by a circumferentially continuous external bead for securinga dispensing closure, said bead having a flat undersurface perpendicularto an axis of said neck finish, said neck finish having a chamferredinside edge around said open mouth to facilitate attachment of adispensing closure.